Miarus campanulae (Linnaeus, 1767)

Skuhrovec, Jiri, Gosik, Rafal, Caldara, Roberto, Tosevski, Ivo, Letowski, Jacek & Szwaj, Ewelina, 2018, Morphological characters of immature stages of Palaearctic species of Cleopomiarus and Miarus and their systematic value in Mecinini (Coleoptera, Curculionidae, Curculioninae), ZooKeys 808, pp. 23-92 : 58-63

Miarus campanulae (Linnaeus, 1767) Figures 71, 72, 73-74, 75-76, 77, 78-80

Material examined.

9 L3 larvae: 30.07.1939, ex Campanula , Store Dyrehave, Denmark, leg. J.P. Kryger, collected in association with adults, det. Van Emden, coll. British Museum of Natural History (London).

Description.

Measurements (in mm). Body length: 3.80-5.96 (mean 5.20). Body width (metathorax or abdominal segments I–II) up to 1.61. Head width: 0.58-0.64 (mean 0.61).

General. Body slender, C-curved, rounded in cross section (Fig. 71).

Colouration. Brown to dark brown head (Fig. 71). All thoracic and abdominal segments yellowish with distinct asperation (Fig. 71).

Vestiture. Setae on body thin, slightly from dark orange to brown, distinctly different in length (minute to very short or long to very long) distinct asperate.

Head capsule (Fig. 72). Head almost round, very slightly flattened laterally. Frontal sutures narrow and loosened, but distinct. One stemma (st), in the form of a large pigmented spot. Des1-3 and des5 long; des4 absent (Fig. 72). Fs1 long; fs2 and fs3 absent; fs4 and fs5 long (Fig. 72). Les1 and les2 as long as des5; both ves short. Epicranial area with two pes.

Antennae bearing one very long conical sensorium, and basal membranous article with four sensilla different in length, three behind conical sensorium, and one ahead of it (Fig. 73).

Clypeus (Fig. 75) approximately 2.5-3 times as wide as long with two short to very short cls, localized posterolaterally, cls1 slightly longer than cls2, and one sensillum between them; anterior margin sinuate.

Mouthparts. Labrum (Fig. 75) less than two times as wide as long, with three piliform lms, different in the length; lms1 located medially, lms2 located anteromedially, and lms3 located anterolaterally; lms1 long, lms2 medium size, and lms3 distinctly shorter than the previous two; no one distinctly reaches labral margin. Epipharynx (Fig. 76) with three long finger-like als, all of identical in length; with two ams in different length, ams1 piliform of medium size, and finger-like short ams2; without mes; labral rods (lr) indistinct, slightly elongated, oval. Mandibles (Fig. 74) bifid; bearing with two setae of medium to long size, piliform, both located apically. Maxilla (Fig. 77) stipes with very long stps and pfs1, long pfs2, very short to minute mbs, and one sensillum close to mbs; mala with six finger-like dms, different in lengths: first very long (as long as pfs1), next medium size; five vms, different in length, two setae medium size, and three setae very short. Maxillary palpi: basal palpomere with one short mxps and two sensilla; distal palpomere with short, cuticular apical processes; length ratio of basal and distal palpomeres 1:0.9. Prelabium (Fig. 77) with one short prms; ligula with two very short to minute ligs; premental sclerite narrow, ring-shaped. Labial palpi with two palpomeres; length ratio of basal and distal palpomeres 1:0.8; each of the palpomeres with one sensillum, distal palpomere with short, cuticular apical processes. Postlabium (Fig. 77) with short pms1 located basally, long pms2 located medially and short pms3 located apically; membranous area without any asperities.

Thorax. Prothorax (Fig. 78) with nine very long and one very short to minute prns, small pigmented dorsal sclerite present with seven long prns, this sclerite subdivided in two triangular plates medially; two very long to long ps; and one medium eus. Meso- and metathorax (Fig. 78) with one medium prs, three very long pds; one very long as; two very long and one very short to minute ss; one long eps; one long ps; and one medium to long eus. Each pedal area of the thoracic segments with 5-6 very long pda.

Abdomen. Abdominal segments I–VII (Figs 79-80) with one medium to long prs; two medium to short and one very long to long pds (order: medium/short, very long, medium); one very long and one minute ss; two long eps; one medium to short ps; one medium to short lsts; and one medium to short and one very short to minute eus. Abdominal segment VIII (Fig. 80) with one very short prs; two short and one long to relatively long pds (order: short, long, short); one long and one minute ss; two very long eps; one medium to short ps; one medium to short lsts; and one medium to short and one very short to minute eus. Abdominal segment IX (Fig. 80) with two relatively long and two short to very short ds; two relatively long and sometimes one minute ps; and one relatively long to short and one short to very short sts. Abdominal segment X (Fig. 80) with one very short seta (ts).

Biology.

Larvae live and pupate in the capsules of several species of Campanula ( C. cochleariifolia Lam., C. patula L., C. persicifolia L., C. rapunculoides L., C. rapunculus L., C. rotundifolia L., C. scheuchzeri Vill. C. trachelium L.), and Phyteuma spicata L. where they cause distinct swelling ( Hoffmann 1958; Buhr 1964)

Remarks.

This species has a wide European distribution and is very similar to M. ajugae . Only the examination of the penis allows easy separation of these two taxa. Therefore, as reported in the Remarks of C. ajugae , the discovery of clearly distinctive characters between the larvae of these two species is extremely important. Moreover, larvae of M. campanulae differ from the two other species studied mainly by an epipharynx without mes, and des4 and fs3 absent.